Comparative epidermal leaf anatomy of some Brassicaceae with emphasis on its systematic implication

Some epidermal leaf anatomy characteristicssuch as the absence/of presence trichomes and stomata and trichometypes in adaxial and abaxial leaf surfaceswithindifferent species, subspecies, varieties,and populations are afforded valuable taxonomic characteristicsin theirdetermination. This study aimedto investigate the leaf epidermal characteristics in72 populations belonging to 46 wild and native Brassicaceae taxa collected from central Iran. Theadaxial and abaxial leaf epidermis was examined using light microscopy. Resultsshowed that all studied samples lack crystals in their epidermis. They can be divided into three groups: 1)without trichomes in both adaxial and abaxial leaf surfaces, 2)having trichomes just onthe abaxial side (Lepidium sativumand Sisymbrium irio),and 3)trichomes in both adaxial and abaxial surfaces. Two Choriosporaspecies can be separated by their trichomes. C. ibericahas glandular trichome,while C. tenellahas no trichomes.This study revealed that just epidermal leaf anatomy characters are not sufficient to identify members of the Brassicaceae members, but can be helpful alongwith other features and may support the systematic valueof taxa in this family.